THE HAGUE -- "Bear detection kits" may help crack down on an illegal trade in bear products supplied by Asian farms where animals are locked in cramped cages, a conservation group said on Tuesday.

The portable kits, which use technology similar to that in a home pregnancy test, can isolate bear proteins in traditional Asian medicines in five minutes, according to the World Society for the Protection of Animals (WSPA).

The bear detection kits, developed with a forensic group called Wildlife DNA Services, are far simpler and quicker than existing procedures that require laboratory equipment, it said.

"The activity that takes place in bear farms is inherently cruel and unnecessary," WSPA head Peter Davies said in a statement released on the sidelines of a June 3-15 U.N. conference on wildlife trade in The Hague.

"The kits will help us build even more evidence to help bring an end to the practice," he said. WSPA says it groups animal protection groups and humane societies in 147 countries.

WSPA said that it had found illegal products containing bear bile -- viewed in some countries as a cure for ailments such as eye and liver disorders -- in the United States, Canada, Japan, Taiwan, South Korea, Singapore, Australia and New Zealand.

It said there were more than 7,000 bears in Chinese farms and thousands more in countries including Vietnam and South Korea.

The animals were often kept in cramped cages with tubes inserted into their gall bladders to drain about 100 ml (35.20 fl oz) of bile a day. Many die from the initial operation, or later infections, it said.

Bear farming is legal in countries including China and products can be sold on the domestic market. But WSPA said exports violated international rules.